LG VX9100 Service Manual page 85

VX9100
Check if there is any major difference referring
RFIN_PCS fed up with CW signal
in low gain mode of PAM
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Only for training and service purposes
Start
Check pin 6 , 8 (TP1,2) at U105
To Figure 4.2.2(i) Is it similar?
YES
Check pin 4 , 11 (TP3) at U105 ( Vcc)
whether it is higher than 3.4V.
YES
Check pin3(TP4) at U105(PA_R1 signal)
whether it is lower than 2.2V.
YES
Replace U105
Checking Flow
Checking Flow
YES
NO
NO
Waveform
Waveform
Figure 4.2.2(i)
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PAM circuit is OK. See next page
Check Vcc line
Check PA_R1 line
RFOUT_PCS
LGE Internal Use Only